Is it true that ionic compounds are made from a cation and an anion?

YES!!!

Sodium chloride is aan ionic compound.

NaCl = Na(+) + Cl(-)

The Na(+) is the CATION (The positive charge)

The Cl(-) is the ANION. (The negative charge)'

They have opposite charges so they come together by electrostatic attraction; like the N & S poles of a magnet.

Also the number of opposite charges MUST be equal .

e.g.

MgCl2 = Mg(2+) + Cl(-) + Cl(-) , usually written as Mg(2+) + 2Cl(-)

Notice the magnesium cation has a positive charge of '2' .So there must be two chloride anions of negative charge of '1' each. ( 2 x 1 = 2)